Improvement in treadle mechanisms



B. B. CHANDLER, Jr.

Treadle Mechanisms.

N0. 142,770. Patented SeptembeH6, 1873.

AM. AIME-1 Iii/067M PHIL 00. M X lOSM/PN! s PHMISS/ UNITED STATES ATENT OrFIoE.

BARTLETT B. CHANDLER, JR, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN TREADLE MECHANISMS.

Specification forming part of Letters Patent No. 142370, dated September 16, 1873; application filed July 5, 1873.

To all whom it may concern:

Be it known that I, BARTLETT B. CHAND- LER, Jr., of Boston, in the county of Sufi'olk and State of Massachusetts, have invented a new and useful Improvement in Treadles or TreadleMechanism; and do hereby declare the same to be fully described in the following specification and represented in the accompanying drawings, of Which Figure 1 is an end elevation of my invention as applied to the frame of a sewing-machine. Fig. 2 is a vertical and central section of the same. Fig. 3' is a view of the interior of the pawl-chamber; and .Fig. 4, an inner-end View of the cap-plate of the pawlehamber, showing the annular grooves, and the surfaces in and against which the pawl operates.

The object of my invention is to produce a simple, efficient, and compact apparatus to be used on sewing-machines, lathes, and other machines that are driven by foot-power; and my invention consists in the peculiar construction and arrangement of its operating parts, as hereinafter specified.

In the said drawings, A denotes a flywheel, which is mounted and turns loosely upon a shaft, a, affixed to the end of the frame B, as seen in Figs. 1 and 2. combined pawl-and-spring ease and chaindrum also loosely mounted on the said shaft. The said case is divided into two chambers, b c, the former of which contains a coiled spring, D, one end of which is attached to a pin projecting from the wall of such chamber, and the other to a stud extending from the plate E, which formsa cap or cover to the outer end of the said chamber, and is firmly affixed to the said shaft to. Within the said chamber 0 an eccentric friction-pawl, F, is loosely pivoted, by means of an oblong slot, upon a stud, d, as shown in Fig. 3. G is an annular plate, which is inserted within the outer end of the said chamber 0, and constitutes a cover thereto. 0 is an annular groove formed in the inner face of the said cap-plate, such being made concentric with the axis of the said plate, and to receive the (lie a,

friction-pawl F, which'is so formed and applied that, when the pawl-and-spring case is moved in one direction it shall move freely, Without binding against the walls of such groove but, when the said case is moved in the opposite direction it shall so impinge against such walls as to hold and turn with the pawl-and-spring case, and thus wind up the spring. Furthermore, the said grooveplate G is firmly secured by means of a pin to the said fly-wheel A, and consequently revolves therewith. h is a spring, which rests against the head or free end of the pawl, and thereby serves to prevent too great lateral play thereof. I is a band or chain, one end of which is attached to the periphery of the pawl-and-spring case, which is so formed as to constitute a drum or barrel, f, therefor, its other end being attached to a connectin g-rod, J, which in turn is connected with the footplate or pedal K.

From the above it will be seen that the pawlgroove has a synchronous movement with the fly-wheel, while the pawl affixed to the chain drum or case 0 moves simultaneously therewith, and that the spring and the pawl, being both affixed to the chain drum or case 0, must, of necessity, move in unison therewith.

Having described the construction and application of my said mechanism, its operation is as follows: If we suppose all the parts to be in position, as shown in Figs. 1 and 2- that is, with the band wound upon the drum, and the foot to be applied to the pedal K, and pressed downward with suflicient power to unwind the band I from its barrel, such movement will cause the. pawl to lock against the walls of its groove and coil the spring D with greater tension around the shaft a, the fly-wheel being moved by such action at the same time and in the same direction. Now, by relieving the pedal of the pressure of the foot, suc'h spring will recoil and carry with it the case (J, the pawl releasing its action upon the Walls of its groove under such movement, and running freely therein, and thus will unwind the band from its drum or barrel, while 2 mawo the fly-Wheel, from the momentum it has acquired, continues its revolutions, such revolution being increased to any desired degree by alternately applying pressure to the pedal and relieving the same therefrom.

What I claim as my invention is- 1. The combined drum, spring-and-pawl case 0, constructed and arranged in manner and for the purposes as explained.

2. The combined drum, springand-pawl case 0, friction-pawl F, grooved-plate G, and spring D, in combination with shaft on, flywheel A, band I, and connecting-rod J, said parts being constructed, arranged, and applied to the frame and pedals so as to operate as herein shown and described.

BARTLETT B. CHANDLER, JR. Witnesses:

E. GRIFFITH, W. H. KDVIBALL. 

